1. Field of the Invention
The present invention relates to a method of controlling a washing machine, and more particularly, to a method of controlling a washing machine, which reduces the eccentric rotation of a wash tub by estimating, in advance, the eccentric rotation beyond a tolerance value.
2. Description of the Related Art
In general, a washing machine is an apparatus that removes contaminants adhered to laundry via several operations including, for example, washing, dehydration, and/or drying. In the washing machine, a wash tub, in which laundry such as, for example, clothing or bedding (hereinafter referred to as “fabric”) is accommodated, is rotated in a water storage tub so that contaminants adhered to the fabric are removed.
The washing machine conventionally performs, in sequence, the supply of water into the water storage tub, washing or rinsing to remove contaminants adhered to fabric via rotation of the wash tub, the drainage of water from the water storage tub, and dehydration of the fabric via high-speed rotation of the wash tub. A dehydration operation requires higher speed rotation than in a washing or rinsing operation.
However, when the fabric is collected on one side inside the wash tub in the dehydration operation, the wash tub may rotate eccentrically, thus causing excessive vibration and noise as well as collision between the wash tub and the water storage tub or between the water storage tub and a casing. In addition, the wash tub has difficulty in reaching a predetermined rotational speed required for the dehydration operation. Therefore, the Related Art 1 and the Related Art 2, described below, implement fabric dispersion by sensing the extent to which the wash tub rotates eccentrically (hereinafter, referred to as “eccentric rotation degree”).
In the Related Art 1, after the water inside the water storage tub is drained, the rotation of the wash tub is accelerated in order to perform a dehydration operation, and the eccentric rotation degree of the wash tub is sensed. When the eccentric rotation degree is a preset tolerance value or less, dehydration is performed by accelerating the wash tub to a higher speed. When the eccentric rotation degree exceeds the preset tolerance value, it is judged that fabric has collected on one side inside the wash tub or that multiple pieces of fabric agglomerate together. Thus, water is again supplied into the wash tub, and the wash tub is alternately rotated in opposite directions so as to disperse the fabric, and thereafter the eccentric rotation degree is sensed while again accelerating the rotation of the wash tub.
In the Related Art 2, the rotation of the wash tub is accelerated while the water inside the water storage tub is drained in order to perform a dehydration operation, and the eccentric rotation degree of the wash tub is sensed. When the eccentric rotation degree is a preset tolerance value or less, dehydration is performed by accelerating the wash tub to a higher speed. When the eccentric rotation degree exceeds the preset tolerance value, the drainage of water from the wash tub is stopped, fabric is dispersed using the water remaining inside the wash tub, and thereafter, the eccentric rotation degree is sensed while again accelerating the rotation of the wash tub.    Related Art 1: Korean Patent Laid-open Publication No. 10-2011-0009923 (published on Jan. 31, 2011)    Related Art 2: Japanese Patent Laid-open Publication No. 2014-8313 (published on Jan. 20, 2014)